Melasma can fade, but the AAD says it is sometimes extremely difficult to treat.
When it fades
The AAD says that when you deliver your baby or stop taking the medication, melasma can fade.
When it does not
The AAD also says that sometimes, melasma is extremely difficult to treat.
Three patient pages on the condition
Three patient pages cover the condition in plain terms: the MedlinePlus encyclopedia entry on melasma, the AAD melasma overview, and the DermNet page on facial pigmentation.
Watching for fading after a trigger ends
The answer changes when the trigger does. Ending a medication or finishing a pregnancy is the moment to check whether the patches are fading.